The overall objective of this research program is to provide further insight into the basic mechanisms through which insulin regulates glucose transport in isolated human adipose cells from lean normal subjects and to further define the factors responsible for the development of "insulin resistance" in the tissues of non-insulin dependent diabetic abd obese patients. Studies will be undertaken to 1) characterize and quantitate the number of glucose transport systems in human adipose cells obtained from lean-normal subjects and 2) examine whether alterations in adipose cellular glucose transport, and in particular in the newly described process of translocation of glucose transport systems, are associated with the insulin resistance of non-insulin dependent diabetic and obese patients. Plasma, high density, and low density microsomal membrane fractions will be prepared from isolated human adipose cells, and the number and distribution of glucose transport systems will be determined by using the specific D-glucose-inhibitable cytochalasin Beta-binding assay. These studies will hopefully provide further knowledge on the basis mechanism of insulin action in normal and pathophysiologic states, knowledge which is essential for better understanding the insulin resistance of many non-insulin dependent diabetic and obese patients, and for developing a more rational and successful therapeutic approach to these conditions.